Centre Number Candidate Number Name UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS General Certificate of Education Ordinary Level 5090/06 BIOLOGY Paper 6 Alternative to Practical October/November 2006 1 hour Candidates answer on the Question Paper. No Additional Materials are required. READ THESE INSTRUCTIONS FIRST Write your Centre number, candidate number and name on all the work you hand in. Write in dark blue or black pen. You may use a soft pencil for any diagrams, graphs, music or rough working. Do not use staples, paper clips, highlighters, glue or correction fluid. Answer all questions. At the end of the examination, fasten all your work securely together. The number of marks is given in brackets [ ] at the end of each question or part question. For Examiner’s Use 1 2 3 Total This document consists of 8 printed pages. SP (SC/CGW) T18246/4 © UCLES 2006 [Turn over www.xtremepapers.net For Examiner’s Use 2 1 Fig.1.1 shows a section of a flower. petal sepal Fig. 1.1 (x 3) Fig.1.2 shows a different type of flower. Fig. 1.2 (x 3) (a) Select two structures that produce different reproductive cells and can be seen in Fig. 1.1. (i) Label these structures on Fig. 1.1 with the letters A and B. [1] (ii) Label clearly where these structures are found in Fig. 1.2, using the letters A and B. [1] (iii) Complete Table 1.1 so that each structure is related to its function. Table 1.1 name function A B [4] © UCLES 2006 5090/06/O/N/06 www.xtremepapers.net 3 (iv) Complete Table 1.2. to show three ways in which the two flowers can be seen to be different in structure. For Examiner’s Use Table 1.2 flower in Fig. 1.1 flower in Fig. 1.2 1 2 3 [3] (b) (i) Suggest how the flower in Fig. 1.1 is pollinated. ..............................................................................................................................[1] (ii) State two reasons for your answer in (b)(i) that are features that can be seen in Fig. 1.1 . .................................................................................................................................. ..............................................................................................................................[2] (iii) Suggest two more features that cannot be seen in Fig. 1.1 that are also typical of this method of pollination. .................................................................................................................................. .................................................................................................................................. ..............................................................................................................................[2] (c) Suggest one way by which a flower might be able to avoid self pollination. .......................................................................................................................................... ......................................................................................................................................[1] [Total : 15] © UCLES 2006 5090/06/O/N/06 www.xtremepapers.net [Turn over For Examiner’s Use 4 2 Fig. 2.1 is a photomicrograph of a section of mammalian skin. Fig. 2.1 (x 50) Fig. 2.2 is a drawing that shows some of the structures that can be seen in Fig.2.1 epidermis dermis X sweat gland subcutaneous fat Fig. 2.2 (a) (i) Suggest why only one complete hair follicle is visible in Fig. 2.1. ............................................................................................................................. [1] (ii) State one function of the secretion from the gland that opens into the hair follicle. ............................................................................................................................. [1] © UCLES 2006 5090/06/O/N/06 www.xtremepapers.net 5 (iii) Indicate, on Fig. 2.2, by means of a line labelled ‘H’, where another hair almost became part of the section. [1] (iv) Indicate, on Fig. 2.2, by means of a line labelled ‘M’, a muscle that contracts to make a hair become erect. [1] (b) (i) For Examiner’s Use Suggest why the sweat gland appears as a group of small circular structures. .................................................................................................................................. ............................................................................................................................. [1] (ii) The layer marked ‘x’ on Fig. 2.2 is constantly dividing to produce new cells. State the type of division that is involved ..............................................................................................................................[1] (c) The fatty tissue in the skin helps to maintain constant body temperature by providing insulation. thick lid clock thin walled plastic beaker thin lid measuring thermometer cylinder Kettle (boiling) thick walled plastic beaker Fig. 2.3 (i) Plan an investigation into the effect of insulation on heat loss, using only the equipment shown in Fig. 2.3. .................................................................................................................................. .................................................................................................................................. .................................................................................................................................. .................................................................................................................................. .................................................................................................................................. .................................................................................................................................. ..............................................................................................................................[3] © UCLES 2006 5090/06/O/N/06 www.xtremepapers.net [Turn over 6 (ii) Suggest two ways in which this investigation could be improved, to make the results more reliable. 1 ............................................................................................................................... .................................................................................................................................. 2 ............................................................................................................................... ..............................................................................................................................[2] [Total : 11] 3 Fig. 3.1 shows a potted plant that is sealed inside a transparent, airtight bag. transparent, airtight bag valve for taking air samples airtight bag over pot Fig. 3.1. • • • The plant, enclosed in its airtight bag, was placed on the ground, in a forest, for 48 hours. A small sample of the enclosed air was taken every six hours. The carbon dioxide concentration of each air sample was measured and recorded in Table 3.1. © UCLES 2006 5090/06/O/N/06 www.xtremepapers.net For Examiner’s Use For Examiner’s Use 7 Table 3.1 time / h carbon dioxide concentration / arbitrary units 0 (midnight) 10 6 13 12 (noon) 8 18 4 24 (midnight) 9 30 12 36 (noon) 8 42 4 48 (midnight) 10 (a) Construct a graph, on the grid provided, from the information in Table 3.1. [4] © UCLES 2006 5090/06/O/N/06 www.xtremepapers.net [Turn over For Examiner’s Use 8 (b) • • Next day the plant in the transparent bag was taken out of the forest and was placed in full daylight. After three hours in full daylight the carbon dioxide concentration was measured and found to be 0 arbitrary units. (i) Explain why this reading was 0. .................................................................................................................................. .................................................................................................................................. ..............................................................................................................................[2] (ii) Explain why the carbon dioxide concentration rose at certain times during this investigation. .................................................................................................................................. .................................................................................................................................. ..............................................................................................................................[2] (c) In a similar experiment a leaf was tested for the presence of starch and the presence of reducing sugar. Describe how you would carry out these tests. starch : .......................................................................................................................................... .......................................................................................................................................... ..................................................................................................................................... [3] reducing sugar: .......................................................................................................................................... .......................................................................................................................................... ..................................................................................................................................... [3] [Total : 14] Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the publisher will be pleased to make amends at the earliest possible opportunity. University of Cambridge International Examinations is part of the University of Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge. © UCLES 2006 5090/06/O/N/06 www.xtremepapers.net